<p *ngIf="warningtext" class="text-danger">{{warningtext}}</p>
<mat-list>
    <mat-list-item *ngFor="let monitor of Monitors">
        <mat-checkbox (change)="checked($event, monitor)" [checked]="isChecked(monitor)">{{monitor.Name}} {{monitor.Width}}x{{monitor.Height}}</mat-checkbox>
    </mat-list-item>
</mat-list>